Various Mode Heat Transfer

AJ Baker, University of Tennessee, Knoxville

Consider an array of heated tubes submerged in a vessel with fluid flowing past them. Neglecting end effects, the flowfield can be assumed 2-D in planes with normals parallel to the tube axes. Further, for modest fluid onset velocity, a steady state solution can be sought.

This example comes from the textbook "The Computational Engineering Sciences" by A.J. Baker.

Objectives of this problem:

1. Become familiar with the COMSOL Multiphysics environment and its graphical user interface.
2. Appreciate the role of the Reynolds and Nusselt non-dimensional groups on heat transfer characterization.
3. Generate simulations for natural, mixed and forced convection heat transfer by adjusting the Reynolds number Re.
4. Perform a mesh refinement study for each class of heat exchange, solution-adapted if necessary, hence estimate the mesh required for each solution to be engineering accurate.
5. Detail the generated heat transfer mode differences graphically and quantitatively and report the results.

User Comments

James Freels
Aug 11, 2009 at 8:42pm UTC

The model file provided is set up for a time-dependent (transient) solution. I attempted to solve this problem in the time-dependent mode, but was not successful. I believe the author intended to solve this problem as a steady-state problem which, indeed, does converge as expected. The default adaptive-mesh solution also works fine on this problem yielding a dispersion-free solution. The variation in Re also produced the expected results. Some interesting variations I tried included to convert the problem from dimensionless to SI units (easily done), using PARDISO solver, and the use of artificial dissipation under the stabilization menu. This is a very interesting problem; particularly the inability to obtain a transient solution here.